Adrian Del Castillo, Spencer Giesting named Diamondbacks’ Minor League Players of the Month in May

The honors aren’t all that surprising. Del Castillo was named the Pacific Coast League Player of the Month and Giesting narrowly lost out the Northwest League Pitcher of the Month award to his teammate Joe Elbis. Both prospects, who weren’t highly ranked entering the 2024 season, are enjoying a breakout year that’s put them on the map. Del Castillo was not ranked by MLB, 29th on Baseball America, and 36th by FanGraphs while Giesting only comes on FanGraphs list at No. 37. The former has since joined MLB’s Top 30 list upon Slade Cecconi’s graduation in April.

Del Castillo hit .359 with five home runs, 20 RBI, and a 1.053 OPS in May. He led the Pacific Coast League with 37 hits and 66 total bases. His .359/.412/.641 batting line for the month adds up to a 154 wRC+, or 54% more productive than the average PCL batter. His .359 average, 10 doubles, and .641 slugging percentage rank second, and his 1.053 OPS ranks fourth. On the season, he’s putting up a .335/.389/.613 slash line with a minor league-leading 25 doubles, 11 home runs, and a 141 wRC+. He’s knocking on the door for a big league opportunity, depending on how much patience the Diamondbacks have with Tucker Barnhart’s bat.

Giesting was 3-1 with a 1.41 ERA and a 40-to-7 strikeout-to-walk ratio in 32 innings. It’s continued a trend of dominance for the 6’4″ left-hander in 2024, who is pounding the strike zone with effectiveness with a low-90s fastball and a plus slider. A former 11th round selection out of UNC Charlotte, he’s having a great season with Hillsboro in his Age 22 season with a 1.70 ERA and a 59-to-11 strikeout-to-walk ratio in 53 innings. He’s a candidate to get promoted to the team’s Double-A affiliate in Amarillo shortly.